Insulator



June 1925.

AUSTIN SULATOR Filed Dec. 6, 1920 2 Sheets-Sheet 1 iazza a 227 y June 23, 1925.

A. O. AUSTIN INSULATOR Filed Dec. 6, 1920 2 Sheets'$ heet 2 175067230 (2% cfl M5;

Patented June 23, 1925.

UNITED- STATES 1,543,313 PATENT OFFICE.

ARTHUR O. AUSTINQOF BARBEBTON, OHIO, ASSIGNOR, BY MESNE ASSIGNMENTS, TO THE OHIO BRASS COMPANY, OF MANSFIELD, OHIO, A. CORPORATION OB. NEW

JERSEY.

INSULATOR.

Application filed December 6, 1920. Serial No. 428,440.

To all whomit may concern:

Be it known that I, ARTHUR O. AUSTIN, a citizen of the United "States, residing at Barberton, in the county of Summit and State of Ohio, have invented certain new and useful Improvements in Insulators, of which the following is a specification.

This invention relates to electrical insulators and especially to the construction of joints connecting arts of such insulators, and has for its ob ect the provision of de vices of the class described in which the mechanical and electrical stresses will be distributed and detrimental concentration of such stresses avoided and which shall be of improved construction and operation.

The invention is exemplified in the combination and arrangement of parts shown in the accompanying drawings and described in the following specification, and it is more particularly pointed out in the appended claims.

In the drawings,

Fig. 1 is a part elevation and part vertical section of an insulator showing one embodiment of the resent invention.

Figs. 2 an 3 are sectional views of metallic parts of insulators showing modifications of the invention.

It is desirable in the construction of insulatorshaving metallic and dielectric parts that the connecting joint between the parts shall be so constructed that the stresses transmitted from one to the other shall be distributed throughout the joint and not concentrated at any particular portion thereof. In my prior application, Serial No. 314,875 I-have shown Various forms of insulator pins arranged to rovide'a yielding joint that will proper y distribute the stresses transmitted rom the pin to the insulator. The present invention contemplates an improvement over the form shown in the application referred to, and it Wlll be readily understood that the features of the invention although shown as applied to a pin for suspension insulators, is equally applicable to the support for pin type and other insulators and may be applied to the cap as well as the internal member.

In the drawin the numeral 10 designates the dielectrlc member of an insulator which is secured to a. cap 11 by cement 12 in an well known and a proved manner.

The 'electric member 10 is provided with an internal opening in whicha pin 13 is' fitted and secured in place by cement 14. The internal surface of the insulator 10 to which the cement-14 is secured may be sanded and coated as described in my prior Patent No. 1,284,975.

' The pin 13 has a series of resilient flanges 15 formed thereon, which engage the cement 14 at their outer edges and transmit the stress of the load through the cement to the dielectric member 10. It will be seen that the flanges 15 will yield under the force of the load upon the pin so that the stress will. be distributed to the dielectric member at various points along the pin and the amount of stress distributed ,at any point may be re ulated by the thickness and distribution 0 the flan cs 15. The fllinges are made of desirable width to provide proper resiliency, and it is desirable that the contact between the flanges and the cement 14 shall be confined largely to the outer edges of the flanges in order to take advantage of the resiliency of the flanges. Ifthe cement extended to the bases of the flanges the stresses would be trans mitted to the cement adjacent the pin at points where the yielding property of the flanges would be little or nothing. Furthermore, if the cement were permitted to extend to the central portion of the pin, rings of cement of considerable thickness would thus be formed between the flanges, which due to the unequal coeflicient of the expansion of cement and porcelain, would ex-. ert undue bursting force on the interior of the porcelain member due to temperature changes. It is readily seen, therefore, that it is very desirable to exclude the cement from the space between the flanges near the bases thereof. To do this, a filling of yielding material such as paper, felt or other similar substance may be packed between flanges as shown at 16, the filling extending outwardly to a sufficient extent to permit the outer edges of the flanges only to be exposed. Instead of providing a filling between the flanges at all points, metal rings 17 may be permitted to extend from the pin so as to occupy a portion of the space between the resilient flanges, an opening being left between each flange and the adjacent metal ring, which op ning is filled with a yielding substance 19, which may be wax, paraflin, glue, paint vent a hard bearing surface against the cement at all points of contact. The coating is preferably thinner at the outer edges of the flanges 15 than at other points on the pin, and the unyielding portions of the pin, such as the projection 19 and the outer faces of the rings 17 and the upper end of the pin. may have a relatively heavy :oating in order that the bearing between the pin and the cement will practically all take place at the edges of the flanges. The thickness and distribution of the flanges 15 may be variously regulated to eflect a proper distribution of the stress transmitted from the pin to the dielectric.

In the form of the invention shown in Fig. 2 a metallic ring 17 is interposed between each pair of flanges 15 and the flanges'and rings are made of uniform thickness and spacing. The openings be tween the flanges and the rings are filled with the material 18' with which the pin is coated to completely exclude cement from the interior or core portion of the pin.

In the form of the invention shown in Fig. 8 the flanges 15 are of uniform thickness throughout the length of the pin, but are variably spaced to secure a desired dis tribution of the stresses transmitted and the metal rings 17 which are shown in the drawings as separately formed and attached to the pin body, but which may also be integrally formed like those shown in Figs. 1 and 2 are varied in thickness to correspond to the s aces between the flanges 15". The rings 1t, 17. and 1? in addition to filling the space-between the flanges and thus excluding cement, have other advantages which add to the efflciency of the construction. In the manufacture of the pins there is less metal to cut away when the rings are permitted to remain as shown in Figs. 1 and 2 than there would be if the entire metal were removed between the flanges, thus reducing the work of manufacture. The presence of integral or securely attached rings also reduces the total elongation of the pin under load for the reason that the portion of the pin adjacent the ring is strengthened by the metal in the ring and hence will resist longitudinal elongation to a greater degree. This decreases the relative movgpient of the parts of the pin with relation 0 the insulator and so diminishes the liability of breakage in the insulator and cement. The projecting rings also form a backing for the flanges in case of an ex cessive load on the pin, the force exerted on the flange being transmitted through the coating material between the flange and the ring. This will permit the flange to be made thinner than would otherwise be practical and in this way a better distribution of the load can be secured. The fact that the rings project to a position near the outer edges of the flanges permits ot4coating of yielding material to be interposed between the cement and the pin at a point adjacent the edges of the flanges. This obviates the use of cement within the space between the flanges and yet prevents danger of bursting the dielectric member by expansion of the pin for the reason that the force of expansion is taken up by the yielding coating upon the outer faces of the rings. The rings also act as a screening member for the flanges to prevent concentration of the electrostatic flux emanating from the edges of the flanges. The lines of force tend to concentrate at the restricted port-ions of the conductor, and where these restricted por tions are limited in extent the concentration of the lines of force tends to produce elec trical discharges. The addition of the relatively extensive rings distributes the lines of force and thus avoids danger of such discharges. Although I have shown the invention as applied to suspension insulators, it is readily apparent that it may also be applied to caps, thimbles for pin type in sulators, or pins cemented in pin type insulators, and to various other constructions in which metal and dielectric members are secured together.

One common method of coating pins of the character described is to dip a cold pin into a melted coating substance. The substance adjacent the pin is chilled and solidifies on the pin forming a coating. Where the metal parts are heavy the chilling effeet will be greatest and the coating heaviest, but where the metal part is thin. as at the edges of the resilient flanges, the thin part soon becomes heatedup and only a very thin coating adheres. This automatically secures the desired distribution of the coating material leaving the outer edges of the resilient flanges substantially uncoated, while the heavier flanges and other heavy portions of the pin have a thick coating, and the space between the flanges is filled full by capillary action.

I claim 1. An insulator comprising a dielectric member and a metallic fitting therefor, said fitting having yielding metallic projections arranged thereon the extremities of which are connected with said dielectric member for transmission of stress from one of said members to the other, and additional projections on said fitting interposed between said first-mentioned projections but unconnected with said dielectric member.

2. In an insulator, a dielectric member, a metallic fitting having spaced resilient metallic projections thereon, holding material engagin the extremities only of said resilient pro ections for securing said holding member to said dielectric member, and packing of fibrous filling material disposed in the openings between said projections for excluding the holding material from portions of said openings while permitting yielding movement of said projections relative to one another.

3.' In an insulator, a dielectric member, a holdin member having'spaced peripheral flanges t ereon, cement arranged to engage the outer portions only of said flanges for securing said holding member to said dielectric member, and packing of fibrous fill-v extremities of said resilient projections for securing said holding member to said dielectric member.

5. An insulator comprising a dielectric member, a metallic fitting having spaced resilient metallic projections thereon, supplemental projections on said fitting, means for connecting said dielectric member to the extremities of said resilient projections to transmit stress from one of said members to the other, said supplemental projections being free from bearing on said cement for transmitting force in the direction of the load on said insulator with said connecting means, and yielding material interposed between said resilient projections and said supplemental projections.

6. An insulator com rising a dielectric member, a metallic hol ing member having ielding projections thereon, cement arranged to connect said dielectric member with the outer portions of said yielding projections, and supplemental projections ar ranged adjacent said yielding projections and acting as a flux screen for said yielding projections.

7. The combination with a dielectric member and a metallic fitting therefor, of spaced resilient metallic projections on said fittin plemental projections free from bearing con nection with said dielectric member for transmitting force in the direction of the load on said insulator and interposed between said resilient projections, and a coating of yielding material arranged to cover said supplemental projections.

8. The combination with a dielectric member and a holding member therefor, of spaced resilient flanges on said holding member, supplemental flanges interposedbetween said resilient flanges and terminating shortof the extremities of said resilient flanges, and yielding material arranged to fill the spaces between said yielding and supplemental flanges to exclude cement from said spaces and confine the connection between said dielectric member and said holding member to the extremities of said flanges.

9. The combination with a dielectric member and a metallic fitting therefor, of means for securing said members together and for distributing stresses transmitted from one of said members to the other, said means comprising spaced resilient metallic rojections on said fitting, holding material engaging the extremities of said projections for securing said projections to said dielectric member, supplemental projections on' said fitting arranged to partially fill the space between said resilient projections to exclude cement therefrom, and yielding material interposed between said supplemental projectionsand said yielding projections to fill the. space between said yielding projections not occupied by said supplemental projections.

10. An insulator comprising a dielectric member, a pin for said insulator having longitudinally spaced circumferential flanges thereon for connecting said pin with said insulator, and supplemental circumferential flanges on said pin interposed between said first-mentioned flanges and of less diameter than said first-mentioned flanges.

11. An insulator comprising a dielectric member, a pin for said insulator having longitudinally spaced circumferential resilient flanges thereon, cement for securing said flanges to said dielectric member, supplemental flanges on said pin of less diameter than said resilient flanges, and yielding ma terial for preventing engagement between said supplemental flanges and said cement.

12. An insulator comprising a dielectric member, a pin for said member having unequally s aced circumferentially arranged resilient anges thereon, cement interposed between said in and said dielectric member and arranged to engage the extremities of said circumferential flanges to provide yielding connection between said pin and said dielectric member for distributing the stresses transmitted from one of said members to the other, yielding filling material interposed &

between said flanges to exclude cement from the space between said flanges away from the extremities thereof, and metallic, supplemental projections on said pin extending into the spaces between said flanges and surrounded by said yielding material but free from hearing connection with said cement to supplement said yielding material in fllling the spaces between said flanges and to act as screening members for said flanges.

13. An insulator pin having thin resilient metallic members arranged to carry the working load and heavier supplemental projections for collecting a comparatively thick coating of yielding material when the pin is dipped in said material.

14. An insulator pin having thin resilient projections and alternating with heavier projections arranged to form with the shank of the pin a heavy body portion for collecting a comparatively heavy coating of yielding material when the pin is dipped in such material.

15. An insulator pin having relatively thin projections thereon for supporting the load, and alternating with heavier projections arranged to form with the shank of the pin a heavy body portion for collecting a comparatively heavy coating of yielding material when a cold pin is dipped into melted coating material while the coating on the thin projections is comparatively thin.

In testimony whereof I have signed mv name to this specification on this 30th day of November, A. D. 1920.

ARTHUR O. AUSTIN. 

